The long-term objectives of this project are to elucidate, using physchophysical methods, the relation between the light stimulus incident on the human eye and the visual signals generated by the receptors, and the neural mechanisms that modify these signals as they are transmitted through the retina. The goals of the coming year are (1) To study lateral effects in the control of sensitivity and to use the sensitization paradigm to elucidate basic questions of retinal function such as the first site of chromatic neural interactions and mechanisms controlling temporal and spatial resolution (2) To search for an optical indicator of receptor outer segment activity, potentially valuable clinical application and (3) To examine the sources of variation between individuals color matching functions.